Aircraft landing equipment



March 21, 1939. E KER 2,151,549

AIRCRAFT LANDING EQUIPMENT Filed July 6, 1956 l'nvelntorz Howard B cker,

is Attovheg Patented Mar. 21, 1939 h UNITED, STATE mortar-T LANDING EQUIPMENT Howard L Becker,

Schenectady, N. Y., assignor to GeneralElectric Company, a corporation of New York dpplicationilnlyc, 1936, serial mvaaoio,

comma (c1. zsc-u) My invention relates to aircraft landing equipment.

It is theobiect of my invention to provide im.-. proved equipment of this character with which a 5 pilot upon approaching a landing area in darkness or in fog may obtain a picture of .the area which will assist him in making a desired landing thereon. v

In accordance with my invention I mark the 10 landing area with one or more short wave radio transmitters. Preferably I employ a number of such transmitters which are arranged to mark the boundary of the landing area. The aircraft is provided with apparatus for receiving the short 15 waves from said transmitters which apparatus includes a directive-receiver. Means are provided 'for causing the receiver to scan a selected area such as that toward which the craft is headed and meansoperative in response to the radio w waves received by said receiver are provided for producing a picture visible to the pilot of the transmitter or transmitters.

My invention will be better understood from the followingdescription taken in connection with g the accompanying drawing, and its scope will be pointed out in the appended claims.

Referring to the drawing, Fig. 1 is a view such as might be obtained by a pilot in an aircraft looking forwardin the day time toward a land- :0 ing area marked with radio transmitters, and Fig. 2 is a combined circuit diagram and perspective view of the apparatus including a part of my invention carried by the aircraft.

In Fig.1 I have represented at I a landing area as .such as might be seen by the pilot looking forward from his position in the craft, the area being marked with the radio transmitters 2'. On the instrument board of the'craft I have shown the" end of a cathode ray tube 3 upon which a picture "so is produced or the arrangement oftransmitters 2.

Referring now to Fig. 2 where I have shown the apparatus for receiving the radio waves broadcast from the several transmitters 2 (Fig. 1) and by which the picture of the arrangement of the transmitters is produced, the radio waves from the several transmitters are picked up'by the di-v rective receiver 4 as that receiver is caused to scan a given area which in this case is directly in front of the craft. The receiver l comprises the directive antenna 5 which is mounted within the cylinder or drum 8 and which preferably is provided with the reflector I to increase its directive properties. This drum ismounted on trunnions sup- .5 portedbythe forkt carried bythe shaft l ,which cam is mounted eccentrically on the shaft it will be understood is supported in suitable bearings, not shown. 1

For causing the drum with its enclosed anten-. na to oscillate horizontally the shaft 9 is provided with the arm in having a slot therein which 5 is engaged by the pin H mounted on crank I2 secured to the shaft l3. This shaft is rotated by the motor I to which it is connected through the bevel gearing IS, the shaft It, the bevel gearing H, the shaft l8 and the worm gearing I9. 10 Y At the end of each horizontal swing the drum 1 is tilted slightly up or down by the operation of the same motor M. The means for producing this tilt is shown comprising the lever 2| fulcrumed at .one end to the extension 22 of the i5 fork 8 and having the opposite end connected by a pin and slot connection with the lugs 23 on the drum 6. Connected to an intermediate point of the lever 2! is the rod 24 which'slides in and is concentric with the shaft 8 and has its lower end g vin engagement with the stepped cam 25. This 26, which is connected by the worm gearing 21 with the shaft l8.' The surface of the cam comprises a number of portions 28 which are concentric with u the shaft 28, which portions are connected with each other by the steps 29. As the cam rotates the rod 24 is given an intermittent movement antenna is given these twomover'nents by the same motor ll is so constructed that'the change in tilt of the drum takes place at-the end of each oscillation thereof. Thus during each complete Q rotation of the cam a certain area which the craft is facing is scanned by the directive receiver. It will be understood that'the rate of scanning need not be of such rapidity as is usual in television apparatus since it is necessary only that the pilot .4; shall be able to see images of the radio transmitters sufficiently rapid to form an meant the 'arrangement thereof and hence judge the location of the craft to the landing field.

' The antenna 5 is shown connected through the flexible concentric conductor 30 with the amplifler 3! which is shown provided with the volume control 32. ,The output circuit 23 of the a'mpli-; fler connects with the grid and cathode of thecathode ray tube 3 in the This as transmitters directly visible.

shall be deflected to scan the end 01' the tube.

the scanning movements of sets of deflecting plates 35 and 38 are supplied with variable voltages which vary respectively in accordance with the horizonin synchronism with the drum 6, the two tal and the vertical positions of the drum. .As an example of a device to produce such a variable voltage I have shown the device 31 which comprises two resistors connected in parallel with a battery. One of the two parallel plates 35 con meets with the midpoint of one resistor and the other plate connects with the contact arm 38 which slides on the other resistor and which is secured to the arm l0. Horizontal movements of the drum 8, therefore, cause varying voltages to be applied to the plates 35 in synchronism with the horizontal movements of the drum. A similar variable voltage device 39 connects with the plates 36, the movable contact arm 40 in this case being mounted on one end of the lever 4|, the opposite end of which has a pin and slot connection with the rod 24, plates 36 vary in synchronism with vertical movements of the drum. v

By means of the above-described apparatus a pilot in approaching a landing area, suchas an airport, which is marked in the manner described but which is obscured from view because of fog, clouds or darkness, may obtain a picture of the landing area as marked by the several transmitters such as it might appear were the The cathode ray tube upon which appears the picture is preferably located in a position where it is easily oh- 4 cathode ray thereof whence the voltages applied to the" served by the pilot and the apparatus by which the tube is operated is automatic in its operation requiring no attention from the pilot except possibly to vary the size or focus of the cathode ray by 'adJusting the volume control 32. v

' I have chosen the particular embodiment described above as illustrative of my invention and it' will be apparent may be made without departing from the spirit and scope of my invention which modifications .I aim to cover by the appended claims.

What L claim as new and desire to secure by Letters Patent otthe United States is: v

l. Aircraft landing equipment comprising a I plurality of radio tr'ansmitters'srranged to mark radio receiving apparatus includa landing area,

ing an antenna directive in two planes substantially at right angles to each other carried by said craft, motor mechanism for moving said antenna to cause it' to scan said area successively in spaced paths, a receiver comprising a cathode ray tube, means for varying the intensity oi the in accordance with the output of said antenna and means for producing scanning movements oi the ray corresponding with the movements of said antenna.

2. Aircraft landing equipment. comprising a plurality of radio transmitters arranged to mark a landing area, radio receiving apparatus including an antenna means directive in two planes substantially at right angles to each other carried by said craft, motor mechanism for moving said antenna means to cause it to scan said area successively in spaced paths, as receiver comprising a cathode ray tube, means for varying the intensity orthe cathode ray thereoi in accordance with the output of said antenna means and means for producing scanning movements oi. the ray the movements of said am HOWARD I. BIEKZKIEIIR.

corresponding with tenna means.

that various modifications 

